Republican presidential nominee Donald Trump failed to shore up support among suburban women—a key demographic that has been cool to him—by struggling to deflect Democrat Hillary Clinton’s attack on his treatment of women, strategists in the businessman’s own party said the morning after the first presidential debate.

Mr. Trump opened the first debate of his general-election matchup with an attempt at chivalry, asking his opponent if...

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How Clinton and Trump Fared in First Debate

Hillary Clinton and Donald Trump succeeded in differentiating themselves in the first presidential debate of the 2016 election on Monday, but they also both missed some opportunities. WSJ's Gerald F. Seib explains. Photo: AP